Náboje, stručná historie, nejdůležitější pojmy, konstrukce

HUB
a brief history of the most important concepts of the design.


Long centuries the firearm charged from the front (out of a muzzle loader) so that the barrel lavished dust, slipped her the shot and then through a small opening, zátravkou, the dust ignited. It was slow, the dust could become damp and the charge lying down wasn't much fun. One of the last předovek were weapons percussion, the zátravku was screwed komínek, expertly piston, and put the cup match. After the strike the hammer on a match ignited the combustible fold inside a match, the flame, and charged the powder and the shot was fired. Here, somewhere about the year 1850-60 start the first practically usable attempts to charge as such, and was born such as the charge of Maynard for percussive zadovku. Charge haven't had your match, she is always dressed to the piston, but the gun is charged from the rear of the metal hub and the shooting was faster. From there it was just a short walk to the first single bullets even if you looked a little different than the bullets of today. It's about paper cartridges for jehlovky e.g. Dreyse, Chassepot, and other. It was better than the percussive fervor. The charge had everything needed to function, including matches in each other, thus the shooting was once again faster. The disadvantages of this solution are obvious. And now we come to the single hubs as we know them today. For the purposes of this article, aside from the bullets for the shotgun and the various experiments that are not extended.

Today's modern ammo, with some exceptions, consist of four parts:
- missiles
- propellant powders
- matches
and the shell casings.

This applies to centrefire cartridges (center fire). For ammunition with rimfire percussion (rim fire) is to match fold placed along the whole perimeter of the dna to the extended edge of the shell casing and so the match as a separate part of the meet. Marginal inflammation is used today in a limited number of calibers, such as bullets Flobert, industrial cartridges and also bullets 22 Short and 22 Long Rifle. The last of those rounds are produced all over the world and this is the charge which produces the greatest amount of in comparison with other calibers. In 19. century the situation was different and produced several dozen kinds of ammunition with rimfire percussion.

Shot spherical bullets can be of various constructions and of various materials, according to the purpose for which it was designed. Some of the first shots were of stone, iron and leaden balls (shot spherical). Today we shot wooden, paper and plastic for military practice ammo, missiles neplášťované, poloplášťové and plášťované for hunting and sporting purposes, and cruise missiles, special mainly for military purposes. In the vast majority it's about a cylindrical, front pointed, or rounded shells (projectiles ogival). The easiest plášťovaná bullet has a lead core enclosed in a predominantly tombakovém or iron coat. But there are also projectiles for hunting purposes with more complex structures, which more or less satisfy the conflicting requirements on the behaviour of the projectile in the target. As an example I will give a shot Brenneke TIG company RWS, or the missile TXP business Standard. The shape of the projectile, inter alia, significantly affects its ballistic characteristics. Shot with favorable aerodynamic shapes simply float away. The type and caliber of the projectile may be affected and the legislation of the country. In the US is allowed to hunt short of weapons and projectiles used for this purpose are other than the shot for sport or defensive shooting. Some of the shot military rounds tend to be whole or part color-coded in different armies with different meaning, usually it is a projectile with tracer, armor-piercing, incendiary, or a combination of these properties.

The end of the 19. century ends as well as the use of black powder in the role of a propelling charge in the bullets and begins to for this purpose to use smokeless powder nitroglycerinový or nitrocelulózový. Smokeless powder has against whooping number of advantages, it's got more power, less corrosive effects on the weapon, less weapon pollutes, it is less susceptible to humidity, etc., With the exception of cordite is a smokeless powder in the form of small grains whose shape and size affects the properties of the dust. Grains in the shape of balls are in proportion to the weight of the smaller surface, thus it burns more slowly than the dust platelet or tube.

Matches for centrefire cartridges have undergone a certain development, both in terms of design and in terms of chemical composition. Nowadays they are used practically only primers Boxer and Berdan. If we wanted to initiate a match just by her chamber the firing pin probably would have failed us. The combustible mixture must be violently pinned between cup matches and something called the anvil. At the matches a Boxer is the anvil part of the match, in case matches Berdan is the anvil formed in a bed for the match and is part of the casing. Explosive mixtures are subject to continuous improvement almost from the inception of matches with the requirement for their reliability, nekorozivnost, neerozivnost and recently even nejedovatost. Non-toxic they are on bc. matches Sintox f. RWS, or matches Nontox f. S&B.

The metal casings of modern rounds are produced by the method of a gradual deep drawing mezioperačním annealing on fully automatic machines. As a material for the manufacture of used brass, steel, or for saving costs and weight, and aluminum. Another technology, the vstřikolisech, to produce a casing part or even all-plastic. The casings are different shapes - cylindrical, conical, lahvicové and of different design - with an edge, with the groove or with flange for thickening of the lower part of the casing. The edge or the groove is used to capture the extractors and the subsequent pulling out the casings, or need selhaného bullets from the chamber. The normal cartridge has boosted the bottom shaped like a bed for the match, in the case of small calibre is used matchstick with a diameter of approximately 4.5 mm, for large-caliber guns that can be up to 8 mm. Between the bezel for a match and the combustion space is usually one or two zátravky, which prošlehne flame from the initiated matches to the dust.

The various calibers of ammunition for small arms is a large amount, of the order of several thousand, from rounds of miniature to the hub with high performance designed for african hunts, or special sniper rifle. At one end of the power spectrum is the charge of 4 mm Flobert with the power of 30 J. at the other end then there is a charge of 20 mm Solothurn for a Finnish anti-tank rifle Lahti from the second world war with the performance of the 50 678 J. Many ammunition calibers have long been used, some of us are linked to more than a hundred years and more ammo added every year in an effort to improve the properties of existing ones. As an example of "longevity" can be given the charge of 9 mm Luger in 1902, or originally černoprachý bullet 22 Long Rifle in 1887. An example of new rounds can be, for example, last year, standardized ammo .450 Bushmaster from the USA, or 375 R Verney-Caron from France. To be able to shoot from all sorts of weapons rounds of ammunition produced by different muničkami, it was necessary to these charges in some way unite. About that old either american standard SAAMI or the european CIP although in this case, the european label is not accurate, a member of the CIP is to even Chile. Normalized charge shall meet the dimensional tolerances and shall not exceed the highest permitted pressures in the shot (P max). A lot of new rounds were created simple by enlarging or shrinking the caliber of the existing hub. An example might be the Russian charge of 5.45 x 39, which originated from a military ammo 7.62 x 39 and from the same hub was created and a charge of 9 x 39, see photo. But there are also many non-standard ammunition, the production of which usually does not exceed 100 000 units per year, production even is not a factory and called the wildcat. As an example, the hub Akley, charge Gibbs and very many others. In the vast majority of come battle of the philippine sea from the USA, but even the Czech republic is left completely aside, see the need to charge 22 Vobořil. Sometimes it happens that the wildcat takes hold, it spreads and eventually it is officially normalized.

The days of marking modern civilian ammo with a central passion in the metric system it is quite clear: 7 x 57 R SB is a cartridge caliber 7 mm, the length of the cartridge is 57 mm, the casing's edge and was probably made by Sellier & Bellot in Vlasim. Initials of SB while also used one philippine and one Spanish munička, but it is unlikely that you get their product. The naming of the rounds is only a contractual designation that a real caliber may not agree, it is sometimes the caliber indicates the distance of the fields of the bore and sometimes the distance of the grooves. To make the confusion worse, so the designation of bullets the 30-06 means 30 caliber hundredths eng. inches, and 06 means year 1906, when he was charge introduced in the u.s. army. The more common designation of the older us rounds, but 44-40 Winchester, when the first number is the caliber in hundredths of the English inch and the second number is the weight of the laborovaného dust in grainech, not to be confused with grams, and Winchester is a company that charge introduced to the market. Who else is not enough, so in England with the caliber reported in 0.001 inch, so an example of the use of the English system is to be 577 Snider. Marking military ammo is different, because of the secrecy of the used numerical or letter codes, in some cases, were the hub without signatures. The end of the 19. century had two big european munitions factory with a large production program of your catalogs, with the numerical designation of their products and quite often these numbers appear directly on the casing. If you see a charge with the designation of the GR 56, is an old military hub 11,2 x 60 R Mauser m 1871, made by f. Georg Roth, Vienna or Bratislava, if at the bottom will be a DWM 358, is an austrian Mannlicher 8 x 50 R made f. Deutsche Waffen und Munitionsfabrik, Karlsruhe or Berlin. Very old bullets tend to do that only the manufacturer, either the full name or just the initials, and for identification it is necessary to charge measured.

The identification of bullets by measuring using literature or the internet leads very often to the success, yet it sometimes happens that it is difficult or even impossible to charge correctly classified. There are two reasons for this. In the early days of production were the manufacturing tolerance directly twere, the linear difference of some of the shell casings of the same caliber could be up to 1.5 mm and the second reason is that not all the old charges have survived physically or at least in drawings. For the identification of the measurement it is important to measure with an accuracy of at least 0.1 mm (caliper) the following information:

1) the diameter of the bottom casing
2) the diameter of the casing just above the bottom of the
3) the bullet diameter close to the neck of the casings
4) length of casing

These four data together with the shape of the shell most often to determine the bullets will suffice. The total length of the hub doesn't mean anything, can be used bullets of different length, or you'll find only a shell casing.

About the rounds, it was written a lot of books. This article is just a brief introduction to the basic concepts and problems, if interested, you sure your source of information to find.

Literature:
Ammunition for small arms, ing. Hýkel, ing. Malimánek, Our troops 1998
Cartridges of the World Frank C. Barnes, 4. edition Ken Warner, Illinois, USA 1980
Patronen des 20. When, J.Lenselink, H. Wanting, W.D.de Hek, Motorbuch Verlag, Stuttgart 1993.